It's Sunday evening, and dozens of 20- and 30-year-olds are trundling into the lobby of Jerusalem's Crowne Plaza Hotel. Some have rucksacks on with sneakers dangling down. Others are pulling Tumi designer rolling bags. Some have tzitzit hanging out or kippot on their heads. Others are in skimpy summer dresses. At least two have mohawks. All of them, says philanthropist Lynn Schusterman, under whose auspices they have gathered here, are future Jewish leaders.

This week, for the seventh year running, ROI - one of the Charles and Lynn Schusterman Philanthropic Network's flagship projects - brought together an eclectic mix of 150 activists, leaders and "change-agents" from around the world for four days of intensive brainstorming, networking and mentoring.

Each one came with a project - half baked, half-realized or even half-completed - and is looking for inspiration, guidance and know-how.

Alison Laichter from New York has created the first-ever grassroots and community-led meditation center with inspired holiday workshops on offer (Think: "Getting in the mood for Hanukkah" ); Andres Knobel from Buenos Aires organizes informal potluck dinners - no Middle East chat allowed - for Arabs, Muslims and Jews; Bar Peled from Jerusalem is working to get young cool people to stop leaving the capital city; and Beril Elhadef from Istanbul launched "Jewlicious Turkey," the Turkey leg of the Jewlicious.com blog where all things fun and hip and Jewish in town are shared.

But what do you do when you can't get enough funding? Where do you go if you realize passions have waned? How do you stay motivated? Communicate your message to a larger public? Attract Jews from the lesbian, gay, bisexual and transgender community to your events? Best use social media?

The answer to all these, the friendly mentors here will tell you, is: "Turn to your ROI community and ask!"

Throw out your question, any question, the moderators encourage, pacing around the ballroom with a microphone at the start of a so-called "Break Out" session. And they do. Oh these future leaders do: "Is kashrut just a moneymaking racket?" someone wants to know. "How do we deal with Jews who reject Israel because of its policies?" another asks. The questions come fast and furious. "Can flash mobs make a difference?" Hm. Tricky. "What is considered Jewish art?" "How do we define Jewish suffering?" "Bring peace?" Even the combined powers of ROI might be challenged sometimes.

Like many other ROI-ers, Jeremy Hulsh, who attended the very first conference, had heard about it from a friend of a friend and was not really clear what he was getting into.

"I understood it was a summit for people doing good things for Israel. I thought that if they dug my idea, they would give me money," he recalls.

He showed up with a "sort-of" idea written on the back of a napkin, and came out with a plan. For, while ROI did go on to award him several grants, as it does most all conference participants, it also offered him, he says, the tools, connections, confidence and support to begin his NGO, Oleh! Records. "Which, basically, is my life now," he says. Oleh!

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